Per Mertesacker is entrusted with the job of collecting fines from Arsenal players in breach of club discipline but the German may find himself going cap in hand to manager Arsene Wenger for his place in the team.

As Brentford fans filtered out of Griffin Park last night and the prospect of an FA Cup tie with Chelsea sank in, they had every reason to be in good voice.

“Champions of Europe, we’re coming for you,” echoed around the ground after Clayton Donaldson’s late winner booked a fourth-round home clash with Rafael Benitez’s side.

Chelsea will, of course, be overwhelming favourites but Brentford can certainly give them an uncomfortable match a week on Sunday.

Third in League One and now unbeaten in 14 games at home, the Bees are playing with a confidence that suggests they will not fear their Premier League opponents.

Brentford assistant manager Alan Kernaghan said: “We know it will be difficult, they are the Champions League holders but if we go about the game plan we come up with we will be in with a chance. We are capable of giving them a game.”

Manager Uwe Rosler, 44, who signed a new two-year contract last week, has built a team comfortable in possession, organised in defence and dangerous in attack.

Harry Forrester and top scorer Donaldson are players capable of hurting a Chelsea team still finding their feet under interim boss Benitez.

Both impressed from the off against Southend last night as the hosts took a deserved lead through Paul Hayes after 26 minutes.

The Bees would have been out of sight before the break had it not been for the heroics of Southend goalkeeper Paul Smith. Brentford had 29 shots on target but, on his return to his former club, Smith made a string of wonderful saves including a one-handed penalty stop to deny Forrester.

Barry Corr headed the League Two side level but Donaldson’s deflected effort in the 76th minute booked Brentford a first meeting with their west London neighbours since 1950.

Rosler banned his squad from talking about Chelsea before last night but the players are now understandably excited at the prospect of facing the FA Cup holders.

Forward Hayes said: “It will be a fantastic occasion. You are not going to get a bigger tie than playing the European champions and it is a west London derby as well.

“Realistically, our chances are maybe one in 100 but you never know. They’ve got a very good squad so it will be interesting to see how we fare.

“When the draw came out we were confident we had enough to get through but we had to make sure that we turned up against Southend. I am sure Chelsea will not worry too much about their opponents but we want to test ourselves against Premier League players. It will be a great tie.”

The televised game is expected to earn Brentford at least £300,000, some of which will be given to Rosler to strengthen his squad for this season’s promotion push.

Before Chelsea visit Griffin Park, Brentford host leaders Tranmere in a top-of-the-table game on Saturday and then welcome Leyton Orient next Tuesday.

Kernaghan said: “We are fortunate we’ve got the League leaders coming here on Saturday, so there is no time to even think about Chelsea. It will be the week prior to the Chelsea game that we start thinking about it.

“When that game comes around it will be a good occasion but there is plenty of time before then and a lot of points for us to pick up.”

Flying high in League One, an FA Cup tie with Chelsea on the horizon and plans to move into a new 20,000-capacity stadium going on show tomorrow, those Brentford fans making their way home last night could be forgiven for their optimism.